Governments have created post offices for collecting, sorting and distributing letter mail, flats and packages (mail). The post office typically charges mailers for delivering the mail. Mailers may pay the post office for its service by purchasing a stamp, i.e., a printed adhesive label, issued by the post office at specified prices, that is affixed to all mail to show prepayment of postage. Going to the post office to purchase stamps that are going to be placed on mail is a labor-intensive endeavor. Thus, stamps typically are used by individuals, small or home offices, and small businesses.
Another means of payment accepted by the post office is mail that is metered by a postage meter. A postage meter is a mechanical or electromechanical device that maintains, through mechanical or “electronic registers” or “postal security devices,” an account of all postage printed, and the remaining balance of prepaid postage, and prints postage postmarks (indicia) or provides postage postmarks (indicia) information to a printer, that are accepted by the post office as evidence of the prepayment of postage. Many postage meters utilize scales to determine the weight of mail. Postage meters may be used by individuals, small or home offices, small businesses, and large businesses.
Post offices and couriers i.e., Federal Express, Airborne, United Parcel Service, DHL, etc. (carriers) provide different services for different types of mail, i.e., first class mail, second class mail, third class mail, priority mail, next day delivery, etc. The cost of the services usually is dependent upon the weight of the mail and the time of expected delivery. Additional charges are applied when mail is delivered from one country to another. Due to various agreements that exist between the posts, the cost of each service varies from country to country. Therefore, in order to apply the proper postage on mail one must know the weight of the mail, the cost of the service, and any extra foreign delivery fee. Sometimes, an individual does not have all of the above information or the proper amount of stamps and has to make a time consuming trip to the post office, during certain postal business hours, to place the proper postage on the mail.
The Universal Postal Union has a complex system that administers contracts between member post offices relating to terminal dues paid between and among different post offices. Terminal dues are the payments made between national postal administrations to cover the costs of handling and delivering international mail. Rates are established by the Universal Postal Union and through bilateral and multilateral agreements. Typically, a post office will charge another post office for the delivery of mail to a recipient within its jurisdiction. For instance, if mail is sent from the United States to the United Kingdom, the United States Post Office will deliver the mail to the Royal Mail, and the Royal Mail will deliver the mail to the recipient. At the end of a predetermined time, the United States Post office and the Royal Mail will tabulate, by weight, all of the mail each post office delivered for the other post office and calculate how much money one post office owes to the other post office.